In a letter to Theresa May the Witham MP said she had acted "with the best of intentions" but accepted it "fell below the standards that are expected of a secretary of state" and "of transparency and openness that I have promoted and advocated".

In response, May said: "Now that further details have come to light it is right that you have decided to resign and adhere to the high standards of transparency and openness that you have advocated".

Patel held 14 undisclosed meetings with Israeli figures, including Israeli Prime Minister Benjamin Netanyahu, who May held a bilateral meeting with last month before knowing about Patel's own meetings.

However questions are now being asked about whether Patel held other meetings that have still not come to light yet.

Labour's shadow deputy leader Tom Watson has written to the Prime Minister for clarity over whether Patel met officials from the British consulate in East Jerusalem over the summer and to explain why that meeting has not been revealed.

Watson wrote: "I have been informed that while she was in Israel, Ms Patel met officials from the British Consulate General Jerusalem, but that the fact of this meeting has not been made public.

"If this were the case, then it would surely be impossible to sustain the claim that the Foreign and Commonwealth Office was not aware of Ms Patel's presence in Israel. The existence of such a meeting or meetings would call into question the official account of Ms Patel's behaviour, and the purpose of her visit."

Watson has demanded details of the meeting and whether Patel was "acting with your authorisation in any of the meetings she held during her visit to Israel".

Labour colleague and shadow international development secretary Kate Osamor added: "After initially denying the allegations, then repeatedly changing her story and failing to disclose all of her meetings, it is right that she has now resigned. But we still need to know what was discussed in these meetings and what Number 10 and the Foreign Office knew and when.

"Theresa May must get control of her chaotic cabinet and decaying government or step aside."

Patel is the second Cabinet minister in a week to have resigned. Former defence secretary Michael Fallon was forced to step down amid sexual misconduct allegations.